Spent Coffee Grounds as Lettuce Fertilizer

I have been working with coffee grounds for a few years now, and find myself consulting on the topic with people from all around the world – on better ways to collect it, use it, or sell it.

This is a long way from where it all started – throwing handfuls of spent coffee grounds into compost and wondering what on Earth I was doing! If you are new to this site, turns out that used coffee grounds are amazing, and hopefully after reading a few of my posts you will be convinced enough to try it yourself.

An even bigger treat than hearing it from me, is hearing it from the academics, hence the reason for this post. What we have here is a quantitative examination into the impact of spent coffee grounds on lettuce production.

According to the authors (Cruz et al 2012), by using spent coffee grounds as an amendment, some of the impacts on lettuce were:

Chlorophylls increased up to 61%.

Lutein and β-carotene levels increased up to 90% and 72%, respectively

Biomass was also improved in the presence of 2.5% to 10% spent coffee

Not bad for a waste product is it? Have a read through from here, and then go try it for yourself!